I would get a doctor's opinion. Depending on the seriousness of your back problem, you could end up in worse shape. Especially with going to the ground. I have had a few try it with bad backs and they usually had to give it up due to going to the ground. If you have a herniated disc, it could make it worse up to and including permanent nerve injury and sequestration of the disc leading to cauda equina syndrome. Get clearance.